We started Seth on some cereal, I guess its a bit like baby rice. We got ours at Boots but you can get some by Heinz or whatever in Asda.
We make it up (its like powder), 2 1/2 teaspoons with 5 teaspoons of water. That might be too much but Seth is a bit of a greedy pig and has been eating that much since we started lol
We also had mashed banana, mashed apple (peel, put into chuncks, cook in steamer for 20 mins & mash) etc on days when he hasn't had his cereal for a bit of variety. When we were away we bought some heinz plum custard pots which he loved too.
We did that for about 2-3 weeks
Then we started giving him tea. Usually about the same amount. he's had, potato, sweet potato, swede, parsnip, carrots, all steamed then mashed up. We usually put between 5 and 7 baby spoonfulls in his dish. We've never pureed anything and he's never had a problem with lumps, but I know a few people arent comfortable with that so do what you feel!!
Also I was a bit worried about him getting a sweet tooth so we decided that he would have sweet things for breakfast (fruit etc) and savoury for tea (veg) so he would get used to both.
We also give him a few sips of water after his meal. he's started reaching for his beaker if he needs some in the middle of his meal now as well. We give him that out of a beaker.
That wont suit everyone because as I say, he is a VERY hungry baby, but thought I might tell you what we did as it might help, and HV was very impressed with what we'd managed considering we'd never really spoken with anyone about it.
We'll be moving him onto 3 meals a day in a couple of weeks as he's getting used to everything now
Good luck, at first it's stressful but after a week or so you just stop worrying about it lol
xxx